The book has been written to simplify the understanding of the orthodontic concepts for the students at undergraduate level who find themselves helpless when the subjects of orthodontics and the growth of craniofacial skeleton are discussed. An attempt has been made to explain the concepts in a simple language. This edition of the textbook, with revised text and layout, aims to help the students in diagnosing an orthodontic problem and classifying its severity so that they are able to manage the condition or guide the patient for comprehensive management by an orthodontist. Many new concepts have been introduced in the field of orthodontics and briefly incorporated in the text, especially early treatment, lasers, microimplants, white spot lesions, evidence–based dentistry, etc. The book focuses on the clinical aspects of the orthodontic conditions and their development as these concepts are to be learnt and understood by the students for their clinical practice.